Essential oils are highly concentrated oils that are extracted from flowers, leaves, roots, and other parts of plants. Typically extracted using steam distillation (a process that involves applying steam until the oil vaporizes), essential oils have the characteristic scent of the plant.In aromatherapy, when molecules of the oil are inhaled or absorbed through the skin, they are said to influence the nervous system and brain areas (such as the limbic system) and affect hormones, brain chemicals, metabolism, and other body functions.Being highly concentrated, the oil shouldn't be inhaled directly from the bottle. To release the oil into the air, a...